摘要
砖红壤是我国植胶区主要土壤类型,该区水土流失严重,养分的流失不仅造成了土壤肥力下降,还会引起地下水体富营养化。在自然降雨条件下,利用大型径流场田间小区试验研究橡胶园土壤中磷和钾素径流流失特征。结果表明:橡胶园土壤磷、钾素的径流流失量受降雨量的影响显著,钾素流失主要发生在雨季来临时前几次大暴雨及施肥后的第一、二场大暴雨;增施磷、钾肥可增加径流水溶性总磷和K+流失量及泥沙结合态磷的流失量,而对泥沙结合态钾的流失量无显著影响;磷和钾的流失均以泥沙携带为主,分别占流失总量的84.06%和70.98%,径流水溶性磷、钾素的流失所占比例较小;在供试条件下,施入的磷肥除部分随地表径流流失外,仍可在一定程度上保持土壤有效磷含量;而施用钾肥大多随降雨径流流失,对土壤速效钾含量无显著影响。
Rubber tracts in China are laid between the north tropics and the south subtropics to enjoy a tropical monsoonal climate, Latosol is the most important soil resources in rubber plantations, most of which are infertile, that lead to slow-growing and low latex yield of rubber tree. It is fearful that, serious soil erosion caused by unreasonable utilization and heavy rainfall make things becoming worse and worse. Phosphorus, nitrogen and potassium losses with runoff are the main contributions to water eutrophication. In order to study how to reduce the nutrients losses and improve the nutrients recoveries, under the condition of natural rainfall, a field experiment treated with different application rates was conducted on rubber plantation by large runoff plots. The results showed that the amounts of P and K losses were affected by rainfall observably, and the K loss mainly occurred during a few times of heavy rain when the rainy season comes before and the first or two heavy rains after fertilization. With the dosage of P and K fertilizer applied increased, the amounts of soluble P and K nutrients showed a positive effect, which was similar to P nutrients combined with runoff sediment, but the K nutrients combined with runoff sediment showed an unconspicuous effect. The soil P and K nutrients mainly migrated with sediment in insoluble forms, proportion for 84.06% and 70.98% separately, while the amounts of soluble nutrients removed with runoff were every little. Besides part lost with surface runoff, the P fertilizer applied to soil could maintain the soil available phosphorus content level at a certain extent, but the K fertilizer mostly lost with rainfall runoff, it showed no significant effect on soil available potassium at this experiment conditions.
出处
《热带作物学报》
CSCD
北大核心
2012年第9期1540-1547,共8页
Chinese Journal of Tropical Crops
基金
国家现代农业产业技术体系建设专项资金(No.CARS-34-GW6)
中国热带农业科学院橡胶研究所基本科研业务费(No.1630022012003)
关键词
橡胶园土壤
径流场
磷和钾
径流流失
Rubber plantation soil
Runoff plot
Phosphorus and potassium
Runoff loss
